What can be worse than cheating? Simple, Loveland says. It all boils down to "the daily withdrawal and negative interactions that show how selfish we can act, how cold we can be, and how unfair we can treat our partner ... Essentially, looking for our own self-benefit, regardless of how sabotaging it can be for our partner’s needs. This is a mutual dance in most cases." One caveat, though: This doesn't apply to "physical and emotional abuse, where there is a clear victim and perpetuator." If that's the case, "none of this applies to you, and you must seek help."

If you're in a relationship that has hit this type of rough patch, these daily doses of pessimism can slowly rot the partnership. The problem starts "when a couple is engaged in constant negative interaction, and persistent negative thoughts about our partner as selfish, or only out for themselves, unsupportive, or even dismissive of our own needs," Loveland says. "The fundamental issue isn't about communication or problem-solving skills, but about trust for each other."

It's a big deal, Loveland says: "This is the number-one cause of a broken relationship, whether you’re aware of it or not." Called "the secret relationship killer," as coined by Dr. John Gottman (a leading researcher in the field of psychology and relationships), this behavior on the part of one or both members of a couple leads to "daily despair," which doesn't allow for any time for recuperation and repair of the relationship. This can cause it to lose "its special meaning," and ultimately feel replaceable.

How can you recognize this intimacy-killer in your own relationship? These daily negative interactions can look a thousand different ways, but here are a few signs, according to Loveland.

"This betrayal can take many different forms: Putting our career (or other relationships) ahead of our romantic relationship, sharing intimate troubles with others that our partner would find uncomfortable if they knew, not bringing things up or lying in order to 'keep the peace,' negatively comparing our partner to better choices (physically, intellectually, emotionally, you name it), withdrawing affection and intimacy, disrespecting and belittling our partner, or breaking a promise our partner asked of us to trust us."

It might sound straightforward, but these stealthy behaviors can lead to huge problems — and ultimately a breakup. "Among these, a common pitfall occurs, or begins, when someone is trying to avoid conflict," Loveland says. "It’s difficult to admit our most vulnerable feelings, and we may even think it’s an exploding bomb to allow negative feelings to come up, let alone [be] shared."

But this is not the way, Loveland says. Couples can fall into a systemic and damaging routine of sweeping hurt feelings under the proverbial rug. Bringing up issues with one's partner can start to feel like "disturbing the peace" in this case. Eventually, people might tell themselves that "it’s best to just ignore" an issue, instead of risking a fight. Not so: "The danger occurs when the issues go ignored, and we compare our partner to others. Little fibs are thrown as 'harmless' lies." Next, she says, one or both parties "unsurprisingly withdraw emotionally."

This incredibly insidious phenomenon can creep into a relationship, like cold through a window in winter. It takes on so many different forms that it can be hard to even identify or isolate. "Considering that most of us long for belonging and connection," Loveland says, "coldness is also a form of betrayal." Naturally, we all want to feel warm feelings of connectedness in a relationship. "This is something we want frequently, not just on special occasions."

"For some of us, it is difficult to warm up and provide love and support the way our partner needs it. It may take years to get comfortable, and we may never feel comfortable. If our partner is fine with that and likes the same, there isn’t a problem. But for the rest of us, we need to be validated for our hard work in raising the kids, celebrated when we reached an important goal in life, comforted when we have felt let down by others, supported in pursuing our own dreams, and accompanied during grief."

If that's not available in our romantic relationship, the person whose needs feel unmet will begin to experience acute feelings of pain.

"Realistically, we all want connection in our own specific ways when it comes to a promotion at work, a loss of a loved one, daily stressors, etc.," Loveland says. "It’s sometimes difficult to share how we would [ideally want to] feel connected during these times, but such a reward when discovered." This takes work, of course — it requires paying serious attention to one's partner's preferences, and taking action.

And sensitivity is paramount. "One partner may like the big surprise birthday party with all the friends and family, but after the kids arrive, [the other partner] may feel disappointed because he would have preferred a weekend alone without the kids to celebrate," Loveland says. "Or one partner may feel incompetent to comfort their partner during time of grief, but their partner may feel rejected" without comfort. "Without knowing the reason our partner let us down, we may react coldly and withdraw because we have been hurt — for not being appreciated that we invested in a special birthday party, or because we were given space during time of grief," and the like.

Here's another way this negativity can play out in a relationship: As awful as it sounds, "we may take opportunities to take advantage of our partner ... Fairness is what makes a strong relationship." To illustrate this idea, Loveland weighs in on her own marriage:

"My relationship is a bit untraditional. My husband does most of the cooking, and I handle the finances. I do light cooking, but my husband prefers to cook, as he finds it fun and he likes to make his food taste good. On the other hand, I like numbers, spreadsheets, organization, and knowing what dollar goes where (although we are both frugal, if we had to pick who would be the best spender, that would be me). In this case it works for the both of us, and there are no hard feelings. No feelings of betrayal. However, if I were to invest in a nice, fancy TV for me, and not the mountain bike for him, that would be unfair. It’s unfair to take advantage of the other. I’ve seen this when one sits at the table and expects the other to bring the food, the napkins, the silverware, while they just sit and ask for more things. If the partner serving feels like a waiter, then they are being taking advantage of."

So how to avoid this this devastating negativity? Or how to repair a relationship if the behaviors are already in place? First off, it's all about trust, Loveland says:

"When there is trust, there is no need for negative thoughts, suspicious questions, confrontations or constant worry ... With trust, there are no longer the questions in your head that are said by worry or fear: Will he share with me how his day went if I ask him? Will I find new clothes in the closet after she promised me we would save? Will he help me around the house when I’m in recovery? Will she be gentle with our kids when she learns about their grades? Will he cancel our date, or our anniversary, for his work meeting? Will she tell her friends about our last fight? Will he stand up for me in front of his mom? Will she stop nagging me?"

On the flip side, "when we can’t trust our partner to come through, we want to change them so we can get more out of the relationship. In all honesty, we feel deprived, so therefore we become more selfish for our needs."

The good news? "When we trust our partner, the opposite is true. We care about how our partner feels, and we know our partner cares how we feel. We do things that will benefit our partner, not just our selves. We are no longer selfish. The pleasure of making each other happy is much more important than self-gains."

As we all know, no relationship is perfect. It's smart to be realistic about one's expectations, and know that a certain amount of strife is normal in a relationship. "Among the happiest and healthiest relationships, there are still quarrels and serious conflicts, even betrayal," Loveland says. "Don’t let anyone fool you. The difference [between] a thriving and a failing relationship isn’t about what the conflict is, or even how [conflict is handled], but how much trust there is."

Indeed, trust is the answer. Trust, the great salve of many relationship-based issues, "makes the handling of conflict a little bit easier, since we trust our partner isn’t [being] neglectful of our feelings and well-being," Loveland says. "There will be spilled milk. No relationship is free of conflict or mistakes. That’s a fact." But in a healthy, loving, trusting relationship, even a huge fight is OK from time to time. Without trust, though, these awful behaviors can seep in, leading to deep and unremitting feelings of discomfort. When the "secret relationship killer" slowly sneaks in, resulting in "constant negative interaction" and "persistent negative thoughts," there's often no turning back. To avoid such a fate for your relationship, be sure to consciously build trust with your partner on a regular basis — and be careful to avoid negative behaviors such as dismissiveness, selfishness and manipulation.

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